Technical Field
The present invention relates to a heat pump system, and more particularly to a heat pump system having multiple functional modes such as an air conditioning mode, a water heating mode, etc.
Related Art
U.S. Pat. No. 4,766,734A has disclosed a heat pump system with a water heating function. As shown in FIG. 1, the heat pump system includes a compressor 1′, a four-way valve 2′, an evaporator 3′, a throttling element and a condenser 4′, and so on. In order to further provide the water heating function, generally, a heat exchanger 5′ is further disposed on a pipeline connected with an outlet of the compressor. The water in a water chamber 6′ is guided to the heat exchanger 5′ for heat exchanging, to generate hot water with a higher temperature. In the heat pump system, high-temperature refrigerants discharging from the outlet of the compressor 1′ all pass through the heat exchanger 5′ and exchange heat with the water, so that the refrigerants waste a part of heat energy. Thus, if a user only needs a conventional air conditioning mode, instead of the water heating mode, the air conditioning performance is affected in the heat pump system. Therefore, functional modes of the heat pump system are neither mature, nor highly efficient.
In the prior art, a heat pump unit integrated with air conditioning and water heating functions not only uses the heat pump system as shown in FIG. 1, but also uses multiple water systems to transfer heat to a user side or transfer heat to outdoor water source or ground source, thereby making full use of usable energy or releasing unusable energy. The heat pump unit has too many sub systems (including a plurality of water systems and heat pump systems). As a result, on one hand, it has a much higher cost of elements and parts. On the other hand, it further increases complexity on laying pipelines and increases labor cost. What's worse, the more complicated the systems are, the more professional and difficult the repairing and maintenance work will be, so that the heat pump unit is rather inconvenient for being used by users.